Great question. This is documented here: Traffic Sources in short yes you can build an audience to target to Traffic Sources: From Baidu or From Bing or From Google or From Yahoo. Have a look at the screen-shot below.
Hope this helps!
Audience based on search engine traffic sources:
Mihnea Docea | Technical Support Rep, Customer Care | Customer & Employee Experience | Adobe | (:: 1 (800) 497-0335